Cooling and/or heating system for cooling and/or heating plant roots, device for growing plants, and method for cooling and/or heating plant roots

ABSTRACT

A cooling and/or heating system for cooling and/or heating plant roots includes at least one heat transfer element to be disposed in a growth base close to plant roots and a 3D textile through which a fluid can flow and which comprises at least one fluid inlet for admitting the fluid and at least one fluid outlet for discharging the fluid. A device with such a cooling and/or heating system and a growth base for plants, and a method for cooling and/or heating plant roots, where fluid of a determined temperature flows through the at least one heat transfer element for the purpose of cooling and/or heating plant roots.

The invention relates to a cooling and/or heating system for coolingand/or heating plant roots.

It has been found by applicant that it can be efficient from at least anenergy viewpoint for the plant roots to be cooled and/or heated insteadof or in addition to cooling and/or heating a space and/or ambient airin which the plants are located.

More particularly, the cooling and/or heating of plant roots canalternatively or additionally be understood to mean the cooling and/orheating of a growth base in which the plants are planted, such as forinstance soil or a substrate, and the cooling and/or heating of theplant roots thereby. In particular, at least a part of the growth basewhere the plant roots are situated or at least can be situated duringthe growth process of the plants can be cooled and/or heated with thecooling and/or heating system according to the invention.

According to the invention, the cooling and/or heating system of thetype stated in the preamble comprises at least one heat transfer elementto be disposed in a growth base close to plant roots and comprising a 3Dtextile through which a fluid can flow and which comprises at least onefluid inlet for admitting the fluid and at least one fluid outlet fordischarging the fluid.

It has been found by applicant that such a 3D textile can provide a goodand/or efficient heat transfer to the growth base in which the 3Dtextile is disposed and can thereby cool and/or heat the plant rootswell and/or efficiently.

The fluid can be any suitable fluid. The use of a liquid, such as water,can be particularly advantageous because, in the case of a liquid, amore efficient heat transport is possible.

The heat transfer element can particularly be configured to be disposedin or under said growth base, for instance to be buried in or to becovered by the growth base. Alternatively, the heat transfer element canbe received in or be arranged under said growth base, for instance byburying and/or by arranging the growth base over the heat transferelement.

The growth base can for instance comprise soil or earth, or anothersuitable medium for plant growth.

In an embodiment of the cooling and/or heating system the system isdesigned and/or configured to substantially uniformly cool and/or heatthe growth base at least close to the plant roots.

The system can particularly be designed and/or configured to uniformlycool and/or heat at least said part of the growth base where the plantroots are situated or at least can be situated during the growth processof the plants.

An advantage of such an even or uniform cooling and/or heating of thegrowth base is that the plant roots can be cooled and/or heated atsubstantially the same or a uniform temperature.

Substantially uniformly can for instance be understood to mean that atemperature of the growth base is the same substantially everywhere, atleast close to the plant roots or at least in said part of the growthbase. The temperature can here for instance vary by a maximum of ±10°,preferably a maximum of ±5°, in said part of the growth base.

In another embodiment of the cooling and/or heating system the systemcomprises at least one main supply conduit for supplying the fluid and aplurality of sub-supply conduits which are connected on one side to theat least one main supply conduit and are connected on the other side toa stated fluid inlet of one or more heat transfer elements.

An advantage of such a system is that distributed supply of the fluid toone or more heat transfer elements is possible via the at least one mainsupply conduit and the plurality of sub-supply conduits, which ensuresor contributes to the uniform cooling and/or heating of the growth baseand/or the plant roots via the at least one heat transfer element.

In this embodiment the sub-supply conduits branch off from the at leastone main supply conduit.

In this embodiment there can for instance be an elongate heat transferelement with a plurality of fluid inlets disposed distributed over thelength of the heat transfer element, so that the fluid is supplied tothe heat transfer element distributed over the length thereof and theheat transfer element can heat the growth base and/or the plant rootssubstantially uniformly. Alternatively or additionally, in thisembodiment there can be a plurality of heat transfer elements, each withone or more fluid inlets, so that together the heat transfer elementscan ensure or contribute to a substantially uniform cooling and/orheating.

In this embodiment the main supply conduit can be arranged at anysuitable position. It can for instance be arranged in the growth base,so that the main supply conduit contributes to the cooling and/orheating of the growth base and/or plant roots. The main supply conduitcould alternatively be arranged under or above the growth base, forinstance if a contribution thereby to the cooling and/or heating isundesirable and must therefore be prevented or limited.

In practical manner the system comprises at least one main dischargeconduit for discharging the fluid and a plurality of sub-dischargeconduits which are connected on one side to the at least one maindischarge conduit and are connected on the other side to a stated fluidoutlet of one or more heat transfer elements.

The at least one heat transfer element can preferably be disposed underthe plant roots, more particularly almost directly on the plant roots.At such a position the plant roots can be cooled and/or heatedeffectively by the heat transfer element.

In yet another embodiment of the system according to the invention thesystem comprises heating means and/or cooling means for heating and/orcooling the fluid.

The heating means and/or cooling means can be embodied in any suitablemanner. The heating means and/or cooling means can for instance comprisean electric heating and/or cooling element.

Residual heat can for instance alternatively or additionally be used toheat the fluid, or residual fluid of a suitable temperature can bereused in the system according to the invention.

In yet another embodiment of the system according to the invention thesystem comprises temperature setting means for setting a temperature ofthe heating means and/or cooling means and thereby a temperature of thefluid.

The temperature setting means can for instance comprise a temperaturesensor for measuring the temperature of the fluid, wherein the heatingmeans and/or cooling means are controlled on the basis of the measuredtemperature and the set temperature.

In yet another embodiment of the system according to the invention thesystem comprises a container for containing fluid, which containercomprises the heating means and/or cooling means, and wherein thecontainer is connected to the at least one fluid inlet and at least onefluid outlet of the at least one heat transfer element.

An advantage of such a container is that a supply of fluid can be heatedand/or cooled and can thus be kept at a desired temperature.

It can alternatively be the case that the fluid is heated and/or cooledduring transport to the at least one heat transfer element.

In practical manner the system can further comprise control means, suchas for instance a processor, for the purpose of controlling the system.

In another embodiment of the system according to the invention the 3Dtextile comprises two main surfaces extending substantially parallel toeach other at a mutual distance, wherein the main surfaces each compriseat least one textile layer and wherein the main surfaces are connectedto each other by means of a number of pile threads.

The two main surfaces disposed at a distance from each other define aspace therebetween, through which space the fluid can flow. The numberof pile threads is also situated in this space. When the fluid flowsthrough the space, the flow is deflected or even becomes turbulent dueto the presence of the pile threads. It has been found by applicant thatheat transfer between the growth base and the heat transfer element canbe enhanced thereby.

The 3D textile can be manufactured by weaving or knitting the textilelayers of the two main surfaces simultaneously. The number of pilethreads is preferably woven or knitted in directly during the weavingprocess, whereby an integrally woven or knitted 3D textile results. Thepile threads can thus be the same threads as those with which one orboth textile layers are woven.

The textile layers and pile threads can be manufactured from anysuitable material, for instance from a plastic or metal. The textilelayers and pile threads can here be manufactured from the same materialor from different materials. At least some of the pile threads canparticularly be manufactured from a heat-conducting material, so thatthe heat transfer to the fluid can be increased further still. At leastthe pile threads can for instance be manufactured from copper, aluminiumor stainless steel.

In practical manner at least one of the two main surfaces can befluid-impermeable. This can for instance be achieved by providing thetwo textile layers with a fluid-impermeable coating or sealing layer.

The main surfaces can be connected to each other in fluid-impermeablemanner along a peripheral edge. The fluid is hereby unable to leave thespace via the peripheral edge.

The 3D textile can alternatively or additionally be enclosed at leastpartially by a fluid-impermeable frame. The frame can thus for instanceextend round the peripheral edge. The frame can alternatively oradditionally extend over at least one of the two main surfaces.

The invention also relates to a device for growing plants, such as forinstance a greenhouse, comprising:

-   -   a cooling and/or heating system as described above on the basis        of one or more of the described embodiments and/or with one or        more of the above described features, alone or in any random        combination;    -   a growth base, such as for instance soil or a substrate, for        growing plants therein,

wherein the at least one heat transfer element is disposed in the growthbase at a location close to the plants to be grown therein.

The advantages of such a device are elucidated above on the basis of thecooling and/or heating system according to the invention.

In practical manner the at least one heat transfer element can bearranged fully covered in the growth base, wherein the plants to begrown in the growth base are situated above the at least one heattransfer element.

In this way the heat transfer element can cool and/or heat the part ofthe growth base where the plant roots are situated in simple manner.

The invention also relates to a method for cooling and/or heating plantroots, wherein use is made of a cooling and/or heating system asdescribed above on the basis of one or more of the described embodimentsand/or with one or more of the above described features, alone or in anyrandom combination, or a device as described above on the basis of oneor more of the described embodiments and/or with one or more of theabove described features, alone or in any random combination, andcomprising the step of having fluid of a determined temperature flowthrough the at least one heat transfer element for the purpose ofcooling and/or heating plant roots situated close to the at least oneheat transfer element.

The invention is further elucidated below with reference to theaccompanying schematic figures, in which:

FIG. 1 is a schematic vertical cross-section through a growth base witha cooling and/or heating system according to a first embodiment of theinvention;

FIG. 2 is a schematic top view of the system of FIG. 1, wherein for thesake of clarity only the system is shown, and

FIG. 3 is a schematic top view of a cooling and/or heating systemaccording to a second embodiment of the invention, wherein for the sakeof clarity only the system is shown.

The same elements are always designated in the figures with the samereference numerals, increased by a hundred (100) for the secondembodiment.

FIGS. 1 and 2 show a cooling and/or heating system 1 for cooling and/orheating plant roots 2. System 1 comprises a heat transfer element 3 inthe form of a 3D textile through which a fluid can flow and which has anumber of fluid inlets 4 for admitting the fluid and a number of fluidoutlets 5 for discharging the fluid. As shown in FIG. 1, the heattransfer element 3 is disposed in a growth base 6, such as for instancesoil or a substrate, at a location just below plant roots 2. By having afluid with a relatively low or relatively high temperature flow throughheat transfer element 3 the growth base 6 can be respectively cooled orheated at least in an area of plant roots 2, so that plant roots 2 arerespectively cooled or heated.

As shown in FIG. 1, heat transfer element 3 in the form of the 3Dtextile comprises in this case two fluid-impermeable main surfaces 7, 8,these lying at a distance from each other. Main surfaces 7, 8 eachcomprise a textile layer 9 and a sealing layer 10. It is also possiblefor a plurality of sealing layers 10 to be provided, and/or for asealing layer to continue at least to a position between the fibres oftextile layer 9. In this case textile layer 9 is not fluid-impermeableper se, and sealing layer 10 is. Pile threads 11 extend between thetextile layers 9 of each main surface 7, 8. In this embodiment the mainsurfaces 7, 8 are connected to each other in fluid-impermeable manneralong the edges, in this case by a side edge 12. The 3D textile definesbetween main surfaces 7, 8 and between pile threads 11 a throughflowspace 13 through which the fluid can flow. When the fluid flows throughspace 13, the flow is deflected or even becomes turbulent due to thepresence of pile threads 11. A good heat transfer from the fluid togrowth base 6 can hereby take place, and growth base 6 can be cooledand/or heated efficiently and/or well.

According to an aspect of the invention, system 1 is designed and/orconfigured to substantially uniformly cool and/or heat growth base 6 atleast close to plant roots 2. In this first embodiment of the system 1according to the invention this is achieved at least partly in thatsystem 1 comprises a main supply conduit 20 for supplying the fluid, towhich main supply conduit 20 a plurality of sub-supply conduits 22connect, which sub-supply conduits 22 then connect to a respective fluidinlet 4 of a plurality of fluid inlets 4. In other words, the sub-supplyconduits 22 extend here between main supply conduit 20 and fluid inlets4. Fluid outlets 5 extend on a side of heat transfer element 3 oppositeto the fluid inlets 4, which outlets are connected via respectivesub-discharge conduits 23 to a main discharge conduit 21. In thisembodiment fluid is supplied via main supply conduit 20 and then fed indistributed manner into heat transfer element 3 via the sub-supplyconduits 22 and fluid inlets 4. In heat transfer element 3 the fluidflows through the space 13 shown in FIG. 1 to the other side of heattransfer element 3, and leaves heat transfer element 3 via fluid outlets5, sub-discharge conduits 23 and main discharge conduit 21. Thedistributed supply of the fluid to heat transfer element 3 enables asubstantially uniform cooling and/or heating of growth base 6 to takeplace.

It is noted that FIG. 2 shows only one, substantially elongate, heattransfer element 3. It will however be apparent to the skilled personthat a plurality of optionally elongate heat transfer elements 3 can beprovided. A plurality of elongate heat transfer elements 3 can forinstance be disposed parallel and adjacently of each other so as tocollectively cool and/or heat a relatively large surface area of growthbase 6. The heat transfer elements can have their own main supplyconduit 20 and/or main discharge conduit 21, or they can share a mainsupply conduit 20 and/or main discharge conduit 21.

FIG. 2 further shows that in this embodiment the system 1 has acontainer 24 in which fluid can be stored. It can thus be stated inrespect of container 24 that it functions as a buffer for hot and/orcold fluid. Arranged in the container is a cooling and/or heatingelement 25, using which the fluid can be cooled and/or heated to adesired, and preferably set, temperature. The main supply conduit 20 andmain discharge conduit 21 are connected to container 24 so that fluidfrom container 24 can be supplied via main supply conduit 20 to heattransfer element 3 and can be transported via main discharge conduit 21back to container 24.

It is noted that fluid with a relatively high temperature can besituated at the top of container 24 and fluid with a relatively lowtemperature at the bottom of container 24. It can hereby be advantageousfor the one conduit of conduit 20, 21 to connect to an upper zone ofcontainer 24 and for the other conduit of conduits 20, 21 to connect toa lower zone of container 24, and for a suitable conduit of conduits 20,21 to be used as main supply conduit and the other as main dischargeconduit, depending on whether roots 2 must be cooled or heated.

Means for mixing the fluid can alternatively or additionally be providedin container 24 so that the fluid in container 24 has a substantiallyuniform temperature. In such a case it is possible for conduits 20, 21to connect to container 24 at the same height.

FIG. 3 shows schematically a system 101 according to a second embodimentof the invention. Only the differences from system 1 according to thefirst embodiment of FIGS. 1 and 2 will be described here. For a furtherdescription reference is made to the above description relating to FIGS.1 and 2.

System 101 comprises a plurality of heat transfer elements 103, in thiscase substantially square as seen in top view. Although shown squarehere, the heat transfer elements can also have any other suitable shape.The main supply conduits 120 and main discharge conduits 121 connect viasub-supply conduits 122 and sub-discharge conduits 123 to heat transferelements 103 disposed on either side thereof. In other words, twoadjacent rows of heat transfer elements 103 in each case share a conduit120, 121 disposed therebetween.

FIG. 3 shows no container for containing fluid. If desired, such acontainer can be provided. Alternatively, main supply conduits 120 andmain discharge conduits 121 can be connected directly to the watermains, and the fluid can be cooled and/or heated during transport to theheat transfer elements 103.

Although the invention is elucidated above on the basis of a number ofspecific examples and embodiments, the invention is not limited thereto.The invention instead also covers the subject matter defined by thefollowing claims.

1. A cooling and/or heating system for cooling and/or heating plantroots, comprising: at least one heat transfer element to be disposed ina growth base close to plant roots and a 3D textile through which afluid can flow and which comprises at least one fluid inlet foradmitting the fluid and at least one fluid outlet for discharging thefluid.
 2. The cooling and/or heating system according to claim 1,wherein the system is configured to substantially uniformly cool and/orheat the growth base at least close to the plant roots.
 3. The coolingand/or heating system according to claim 1, comprising at least one mainsupply conduit for supplying the fluid and a plurality of sub-supplyconduits which are connected on one side to the at least one main supplyconduit and are connected on the other side to a stated fluid inlet ofone or more heat transfer elements.
 4. The cooling and/or heating systemaccording to claim 1, comprising at least one main discharge conduit fordischarging the fluid and a plurality of sub-discharge conduits whichare connected on one side to the at least one main discharge conduit andare connected on the other side to a stated fluid outlet of one or moreheat transfer elements.
 5. The cooling and/or heating system accordingto claim 1, wherein the at least one heat transfer element is configuredto be disposed under the plant roots.
 6. The cooling and/or heatingsystem according to claim 1, comprising heating means and/or coolingmeans for heating and/or cooling the fluid.
 7. The cooling and/orheating system according to claim 6, comprising temperature settingmeans for setting a temperature of the heating means and/or coolingmeans and thereby a temperature of the fluid.
 8. The cooling and/orheating system according to claim 6, comprising a container forcontaining fluid, the container comprising the heating means and/orcooling means, and wherein the container is connected to the at leastone fluid inlet and at least one fluid outlet of the at least one heattransfer element.
 9. The cooling and/or heating system according toclaim 1, wherein the 3D textile comprises two main surfaces extendingsubstantially parallel to each other at a mutual distance, wherein themain surfaces each comprise at least one textile layer and wherein themain surfaces are connected to each other by means of a number of pilethreads.
 10. The cooling and/or heating system according to claim 9,wherein at least one of the two main surfaces is fluid-impermeable. 11.The cooling and/or heating system according to claim 9, wherein the mainsurfaces are connected to each other in fluid-impermeable manner along aperipheral edge.
 12. The cooling and/or heating system according toclaim 1, wherein the 3D textile is enclosed at least partially by afluid-impermeable frame.
 13. A device for growing plants comprising: acooling and/or heating system according to claim 1; a growth base forgrowing plants therein, wherein the at least one heat transfer elementis disposed in the growth base at a location close to the plants to begrown therein.
 14. The device according to claim 13, wherein the atleast one heat transfer element is arranged fully covered in the growthbase and the plants to be grown in the growth base are situated abovethe at least one heat transfer element.
 15. A method for cooling and/orheating plant roots, comprising: providing a cooling and/or heatingsystem for cooling and/or heating plant roots, comprising: at least oneheat transfer element to be disposed in a growth base close to plantroots, and a 3D textile through which a fluid can flow and whichcomprises at least one fluid inlet for admitting the fluid and at leastone fluid outlet for discharging the fluid; flowing fluid of adetermined temperature through the at least one heat transfer element tocool and/or heat plant roots situated close to the at least one heattransfer element.
 16. The method of claim 15, further comprising agrowth base for growing plants therein, wherein the at least one heattransfer element is disposed in the growth base at a location close tothe plants to be grown therein.